Phase shifter and working method thereof, antenna, and communication device

Abstract

The embodiment of the present invention discloses a phase shifter and a working method thereof, an antenna, and a communication device. The phase shifter includes: a first substrate and a second substrate arranged opposite to each other, a dielectric layer arranged between the first substrate and the second substrate, a first electrode arranged on a side of the first substrate close to the second substrate, a second electrode arranged on a side of the second substrate close to the first substrate, and a ground electrode arranged on a side of the second substrate away from the first substrate; wherein the dielectric layer includes liquid crystal molecules, and the first electrode and the second electrode are used to control the deflection of the liquid crystal molecules according to a received voltage. The embodiment of the present invention can change the transmission constant of microwaves by arranging liquid crystal molecules between the first substrate and the second substrate and applying voltage to the first electrode and the second electrode, thereby achieving the purpose of phase shifting. The technical solution provided by the embodiment of the present invention reduces the loss, response time and volume of the phase shifter, and improves the performance of the phase shifter.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of phase shifters, and in particular to a phase shifter and a working method thereof, an antenna, and a communication device. Background Art

[0002] Phase shifter is a device that can adjust the phase of microwaves. It is widely used in electronic communication systems and is a core component in phased array radar, synthetic aperture radar, radar electronic countermeasures, satellite communications, and receivers. Therefore, high-performance phase shifters play a vital role in these systems.

[0003] The inventors have found that the existing phase shifters have disadvantages such as large loss, long response time and large size, and cannot meet the rapid development of electronic communication systems. Summary of the invention

[0004] In order to solve the above technical problems, the embodiments of the present invention provide a phase shifter and a working method thereof, an antenna, and a communication device, which can reduce the loss, response time, and volume of the phase shifter and improve the performance of the phase shifter.

[0005] In a first aspect, an embodiment of the present invention provides a phase shifter, comprising: a first substrate and a second substrate arranged opposite to each other, a dielectric layer arranged between the first substrate and the second substrate, a first electrode arranged on a side of the first substrate close to the second substrate, a second electrode arranged on a side of the second substrate close to the first substrate, and a ground electrode arranged on a side of the second substrate away from the first substrate;

[0006] The dielectric layer includes liquid crystal molecules, and the first electrode and the second electrode are used to control the deflection of the liquid crystal molecules according to the received voltage.

[0007] Optionally, the first electrode includes: periodically arranged metal patches, and the second electrode is a microstrip line.

[0008] Optionally, the long axis direction of the microstrip line is the same as the arrangement direction of the metal patches.

[0009] Optionally, the width of the metal patch is 0.5-1.5 mm, the length is less than or equal to 5 times the width of the microstrip line, and the period of the metal patch is less than or equal to 3 mm.

[0010] Optionally, the dielectric layer has a thickness of 5-10 microns.

[0011] Optionally, the ground electrode is a ground wire and is planar.

[0012] Optionally, the liquid crystal molecules are nematic liquid crystal molecules.

[0013] In a second aspect, an embodiment of the present invention further provides a working method of a phase shifter, which is applied to the above-mentioned phase shifter, and includes:

[0014] An electric signal is applied to the first electrode and the second electrode to make the long axis of the liquid crystal molecules parallel to the direction of the electric field between the first electrode and the second electrode.

[0015] In a third aspect, an embodiment of the present invention further provides an antenna, comprising: at least one of the above-mentioned phase shifters.

[0016] In a fourth aspect, an embodiment of the present invention further provides a communication device, including: the above-mentioned antenna.

[0017] The embodiment of the present invention provides a phase shifter and its working method, antenna, and communication equipment, wherein, since in the phase shifter of this embodiment, a ground electrode is provided on the side of the second substrate away from the first substrate, the second electrode on the second substrate and the first electrode form a transmission structure, and the second substrate is a transmission channel, which serves as the main transmission area of ​​microwaves. Moreover, the second substrate material is usually glass, ceramic, etc., and microwaves are basically not absorbed when transmitted therein, so the loss of microwaves can be effectively reduced, and compared with the transmission of microwaves in the layer where the liquid crystal molecules are located, the energy loss is one order of magnitude lower. At the same time, the electric field formed by the voltage applied to the first electrode and the second electrode can deflect the liquid crystal molecules and anisotropy to change the dielectric constant of the dielectric layer, thereby changing the resonant frequency of the microwaves passing through the dielectric layer, that is, changing the phase velocity of the microwaves, and then realizing the phase shift of the microwaves.

[0018] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings are used to provide a further understanding of the technical solution of the present invention and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present invention and do not constitute a limitation on the technical solution of the present invention.

[0020] Figure 1 A schematic diagram of the structure of a phase shifter provided in an embodiment of the present invention;

[0021] Figure 2 A side view of a phase shifter provided by an embodiment of the present invention;

[0022] Figure 3 A top view of a phase shifter provided by an embodiment of the present invention;

[0023] Figure 4A circuit model of a phase shifter provided in an embodiment of the present invention;

[0024] Figure 5 A schematic diagram of the working principle of the phase shifter provided in an embodiment of the present invention.

[0025] Description of reference numerals:

[0026] 10: first substrate;

[0027] 11: first electrode;

[0028] 20: second substrate;

[0029] 21: second electrode;

[0030] 22: ground electrode;

[0031] 30: dielectric layer;

[0032] 110: Metal patch;

[0033] 300: Liquid crystal molecules. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solution and advantages of the present invention more clear, the embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other arbitrarily without conflict.

[0035] The steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions. Also, although a logical sequence is shown in the flowchart, in some cases, the steps shown or described can be performed in a sequence different from that shown here.

[0036] Unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The "first", "second" and similar words used in the embodiments of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words always appear in front of the word element or false detection covers the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0037] At present, most of the phase shifters on the market are ferrite phase shifters and PIN diode phase shifters. Among them, ferrite phase shifters have the disadvantages of bulky size and slow response speed, which are not suitable for high-speed beam scanning; diode phase shifters have high power consumption and are not conducive to being used as lightweight and low-power phased array systems.

[0038] In order to solve the technical problems of high power consumption, slow response speed and large size of the existing phase shifter, the embodiment of the present invention provides a phase shifter and a working method thereof.

[0039] Embodiment 1

[0040] Figure 1 A schematic diagram of the structure of a phase shifter provided in an embodiment of the present invention is shown in FIG. Figure 1 As shown, the phase shifter provided by the embodiment of the present invention includes: a first substrate 10 and a second substrate 20 arranged opposite to each other, a dielectric layer 30 arranged between the first substrate 10 and the second substrate 20, a first electrode 11 arranged on a side of the first substrate 10 close to the second substrate 20, a second electrode 21 arranged on a side of the second substrate 20 close to the first substrate 10, and a ground electrode 22 arranged on a side of the second substrate 20 away from the first substrate 10. The dielectric layer 30 includes but is not limited to liquid crystal molecules 300, and the first electrode 11 and the second electrode 21 are used to control the deflection of the liquid crystal molecules 300 according to the received voltage.

[0041] Since in the phase shifter of this embodiment, a ground electrode 22 is provided on the side of the second substrate 20 away from the first substrate 10, the second electrode 21 on the second substrate 20 and the first electrode 11 form a transmission structure, and the second substrate 20 is a transmission channel, as the main transmission area of ​​microwaves, and the second substrate 20 is usually made of glass, ceramics, etc., and microwaves are basically not absorbed when transmitted therein, so the loss of microwaves can be effectively reduced, and compared with the transmission of microwaves in the layer where the liquid crystal molecules 300 are located, the energy loss is one order of magnitude lower. At the same time, the electric field formed by the voltage applied to the first electrode 11 and the second electrode 21 can deflect the liquid crystal molecules 300, anisotropic, so as to change the dielectric constant of the dielectric layer 30, thereby changing the resonant frequency of the microwaves passing through the dielectric layer 30, that is, changing the phase velocity of the microwaves, and then achieving the phase shift of the microwaves. Optionally, the first substrate 10 and the second substrate 20 may be glass substrates with a thickness of 100-1000 microns, sapphire substrates, polyethylene terephthalate substrates, triallyl cyanurate substrates and polyimide transparent flexible substrates with a thickness of 10-500 microns.

[0042] Specifically, the first substrate 10 and the second substrate 20 may be made of high-purity quartz glass with extremely low dielectric loss. Compared with ordinary glass substrates, the first substrate 10 and the second substrate 20 using quartz glass can effectively reduce the loss of microwaves, so that the phase shifter has low power consumption and high signal-to-noise ratio.

[0043] Optionally, the first electrode 11 may be made of metal such as aluminum, silver, gold, chromium, molybdenum, nickel or iron.

[0044] Optionally, the second electrode 21 may be made of metal such as aluminum, silver, gold, chromium, molybdenum, nickel or iron, or may be made of a transparent conductive oxide.

[0045] Optionally, the liquid crystal molecules 300 are positive liquid crystal molecules or negative liquid crystal molecules. It should be noted that when the liquid crystal molecules 300 are positive liquid crystal molecules, the angle between the long axis direction of the liquid crystal molecules 300 and the second electrode 21 in the specific embodiment of the present invention is greater than 0 degrees and less than or equal to 45 degrees. When the liquid crystal molecules 300 are negative liquid crystal molecules, the angle between the long axis direction of the liquid crystal molecules 300 and the second electrode 21 in the specific embodiment of the present invention is greater than 45 degrees and less than 90 degrees, which ensures that after the liquid crystal molecules 300 are deflected, the microwave propagation constant can be better adjusted to achieve the purpose of phase shifting.

[0046] In this embodiment, in order to better adjust the microwave transmission constant after the liquid crystal molecules 300 are deflected, the dielectric constant of the liquid crystal molecules in the long axis direction is greater than the dielectric constant of the first substrate 10 and the second substrate 20, wherein the specific selection of the material of the liquid crystal molecules 300 is selected based on actual production needs and material costs.

[0047] like Figure 2 and 3 As shown, as a preferred implementation scheme in this embodiment, Figure 2 A side view of a phase shifter provided by an embodiment of the present invention; Figure 3 A top view of a phase shifter provided in an embodiment of the present invention, wherein a first electrode 11 on a first substrate 10 of the phase shifter comprises: periodically arranged metal patches 110, and a second electrode 21 on a second substrate 20 is a microstrip line; a ground electrode 22 on the second substrate and the microstrip line form an output structure, and the second substrate serves as a transmission channel; wherein the arrangement direction of the metal patches 110 is the same as the axis (long axis direction) of the microstrip line.

[0048] In this implementation, the microstrip line can not only transmit microwaves with the ground electrode 22, but also drive the liquid crystal molecules 300 to deflect after an electric field is applied to the microstrip line and the metal patch 110, so that the dielectric constant of the layer where the liquid crystal molecules 300 are located changes, thereby changing the resonant frequency of the microwaves and adjusting the microwave phase. This type of shifter has a simple structure and is easy to implement.

[0049] The reason why the arrangement direction of the metal patch 110 and the axis (long axis direction) of the microstrip line are set to be the same is to increase the area of ​​the overlapping region of the orthographic projection of the metal patch 110 on the second substrate 20 and the orthographic projection of the microwave on the second substrate 20, so as to better control the deflection of the liquid crystal molecules 300. It should be noted that Figure 1 is another side view provided by an embodiment of the present invention, which is a side view viewed from the long axis direction of the second electrode. Figure 2 It is a side view viewed from the short axis direction of the second electrode.

[0050] Specifically, the metal patch 110 is strip-shaped, and the long axis direction of the metal patch 100 is perpendicular to the long axis direction of the microstrip line. Of course, the long axis direction of the metal patch 100 only needs to intersect with the long axis direction of the microstrip line, but it is best to ensure that the long axis directions of each metal patch 100 are the same.

[0051] Specifically, the width w of the metal patch 100 is 0.5-1.5 mm, and the length l is less than or equal to 5 times the width of the microstrip line. The period b of the metal patch 100 is less than or equal to 3 mm. Of course, the selection of the metal patch can also be determined according to the specific size of the phase shifter.

[0052] Optionally, the ground electrode 22 is a ground line and is planar. Specifically, the ground electrode 22 cooperates with the microstrip line to transmit high-frequency signals. Further, the ground electrode 22 covers the entire second substrate 20, as long as the ground electrode and the microstrip line at least partially overlap.

[0053] Preferably, the length of the microstrip line is equal to the length or width of the second substrate 20. If the long axis of the microstrip line is parallel to the long side of the second substrate 20, the length of the microstrip line is equal to the length of the second substrate 20. If the long axis of the microstrip line is parallel to the short side of the second substrate 20, the length of the microstrip line is equal to the width of the second substrate 20.

[0054] Optionally, the dielectric layer 30, that is, the layer where the liquid crystal molecules 300 are located, has a thickness a of 5-10 microns. The dielectric layer 30 provided in the embodiment of the present invention has a relatively small thickness, which can ensure that the liquid crystal molecules can turn quickly and improve the response speed of the phase shifter. The thickness of the dielectric layer in the embodiment of the present invention is set according to actual life process conditions and product requirements, and the specific embodiment of the present invention does not limit the specific value of the thickness of the dielectric layer.

[0055] Optionally, the liquid crystal molecules 300 are nematic liquid crystal molecules, which have large dielectric anisotropy, small absorption loss to microwaves, and the advantage of fast turning speed under electric field, and can further improve the performance of the phase shifter.

[0056] It should be noted that Figure 4The circuit model of the phase shifter provided in the embodiment of the present invention is as follows: Figure 4 As shown in the figure, L0 and C0 are the equivalent inductance and equivalent capacitance of the microstrip line, b is the period of the metal patch, C LC The variable capacitance brought by the introduction of metal patches.

[0057] Where, the phase velocity V p Satisfies the following formula:

[0058]

[0059] From the above formula, we can see that the phase speed is determined by the inductance and capacitance, and the inductance and capacitance are determined by the size of the microstrip line, the size of the metal patch and the surrounding medium.

[0060] According to the parallel plate capacitor formula, the variable capacitance C brought by the introduction of the metal patch LC satisfy:

[0061]

[0062] Where ε0 is the dielectric constant of vacuum, ε r is the relative dielectric constant of the liquid crystal molecules, s is the area facing the metal patch and the microstrip line, and d is the distance between the metal patch and the microstrip line.

[0063] From the formula of variable capacitance, we can know that the variable capacitance C brought by the introduction of metal patch is LC With ε r , s (i.e. ε r The larger s is, the greater C LC The larger the value is); inversely proportional to d (the larger the value is, the greater the value of C LC the smaller).

[0064] The embodiment of the present invention generates an electric field by applying voltage between the microstrip line and the metal patch 110 to deflect the liquid crystal molecules 300, thereby changing the dielectric constant of the layer where the liquid crystal molecules 300 are located, and making the capacitance C between the capacitor metal patch and the microstrip line LC When the microwaves are transmitted, the resonant frequency changes, which in turn changes the phase velocity, thus achieving a phase shifting effect.

[0065] In this embodiment, the phase shifter also includes a driving circuit (not output in the figure), a first signal microstrip line connected to the microstrip line, and a second signal microstrip line connected to the metal patch 110, wherein the driving circuit includes a first voltage signal output terminal that outputs a first voltage signal and a second voltage signal output terminal that outputs a second voltage signal, the first signal microstrip line is connected to the first voltage signal output terminal of the driving circuit, and the second signal microstrip line is connected to the second voltage signal output terminal of the driving circuit.

[0066] When the phase shifter is working, the driving circuit outputs a first voltage signal to the first signal microstrip line and outputs a second voltage signal to the second signal microstrip line. The first signal microstrip line transmits the first voltage signal to the microstrip line, and the second signal microstrip line transmits the second signal to the metal patch 110. An electric field is generated between the microstrip line and the metal patch 110, driving the liquid crystal molecules to deflect.

[0067] Figure 5 The working principle diagram of the phase shifter provided in the embodiment of the present invention is shown below in conjunction with Figure 5 , further describing the working principle of the phase shifter, the specific instructions are as follows:

[0068] The driving circuit outputs a first voltage signal to the first signal microstrip line and outputs a second voltage signal line to the second signal microstrip line. The first signal microstrip line transmits the first voltage signal to the microstrip line, and the second signal microstrip line transmits the second signal to the metal patch 110. An electric field is generated between the microstrip line and the metal patch 110, driving the liquid crystal molecules to rotate so that the long axis of the liquid crystal molecules 300 is parallel to the electric field direction between the first electrode 11 and the second electrode 21. The dielectric constant of the dielectric layer 30 changes, thereby causing a phase shift in the microwaves. The microstrip line and the ground electrode 22 work together to transmit the phase-shifted microwaves.

[0069] Embodiment 2

[0070] Based on the inventive concept of the above embodiments, an embodiment of the present invention provides a working method of a phase shifter, which is applied to the phase shifter provided in Embodiment 1, wherein the method comprises: applying an electric signal to the first electrode 11 and the second electrode 21 so that the long axis of the liquid crystal molecules is parallel to the direction of the electric field between the first electrode 11 and the second electrode 21.

[0071] It should be noted that an electrical signal may be applied to the first electrode 11 and the second electrode 21 at the same time, or an electrical signal may be applied to the first electrode and the second electrode at the same time.

[0072] When the phase shifter is working, the driving circuit applies an electric signal to the first electrode 11 and the second electrode 21, and an electric field is generated between the first electrode 11 and the second electrode 21, driving the liquid crystal molecules to deflect, so that the long axis of the liquid crystal molecules is parallel to the direction of the electric field between the first electrode 11 and the second electrode 21, and the dielectric constant of the dielectric layer changes, thereby causing the microwave to produce a phase shift.

[0073] The working method of the phase shifter provided in the embodiment of the present invention is applied in the phase shifter provided in the first embodiment. At this time, a ground electrode 22 is provided on the side of the second substrate 20 away from the first substrate 10, so the second electrode 21 on the second substrate 20 and the first electrode 11 form a transmission structure. At this time, the second substrate 20 is a transmission channel, which serves as the main transmission area of ​​microwaves. Moreover, the material of the second substrate 20 is usually glass, ceramic, etc., and microwaves are basically not absorbed when transmitted therein, so the loss of microwaves can be effectively reduced. Moreover, compared with the transmission of microwaves in the layer where the liquid crystal molecules 300 are located, the energy loss is one order of magnitude lower. At the same time, the electric field formed by the voltage applied to the first electrode 11 and the second electrode 21 can deflect the liquid crystal molecules 300 and anisotropy, so as to change the dielectric constant of the dielectric layer 30, thereby changing the resonant frequency of the microwaves passing through the dielectric layer 30, that is, changing the phase velocity of the microwaves, and then realizing the phase shift of the microwaves.

[0074] Embodiment 3

[0075] Based on the inventive concept of the above embodiments, an embodiment of the present invention further provides an antenna, which includes: at least one phase shifter.

[0076] Among them, the phase shifter is the phase shifter of the first embodiment of the present invention, and its implementation principle and implementation effect are similar, which will not be repeated here.

[0077] Specifically, the antenna is a liquid crystal antenna. In practical applications, a carrying unit may be further included, such as a carrying plate, and the phase shifter may be arranged on the carrying plate, which is not limited in any way in the embodiment of the present invention.

[0078] It should be noted that the number of phase shifters included in the antenna is determined according to actual needs and is not specifically limited in the embodiment of the present invention.

[0079] Embodiment 4

[0080] Based on the inventive concept of the above embodiment, an embodiment of the present invention further provides a communication device, which includes: an antenna.

[0081] Among them, the antenna is the antenna provided in Example 3, and its implementation principle and implementation effect are similar, which will not be repeated here.

[0082] Specifically, the communication device may be a smart phone, a tablet computer, or a smart computer.

[0083] The drawings of the embodiments of the present invention only involve the structures involved in the embodiments of the present invention, and other structures may refer to the general design.

[0084] For the sake of clarity, in the drawings used to describe the embodiments of the present invention, the thickness and size of the layer or microstructure are exaggerated. It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "under" another element, the element may be "directly" "on" or "under" the other element, or there may be intermediate elements.

[0085] In the absence of conflict, the embodiments of the present invention, that is, the features in the embodiments, may be combined with each other to obtain new embodiments.

[0086] Although the embodiments disclosed in the present invention are as above, the contents described are only embodiments adopted to facilitate understanding of the present invention and are not intended to limit the present invention. Any technician in the field to which the present invention belongs can make any modifications and changes in the form and details of implementation without departing from the spirit and scope disclosed in the present invention, but the patent protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. A phase shifter, characterized in that: include: A first substrate and a second substrate arranged opposite to each other, a dielectric layer arranged between the first substrate and the second substrate, a first electrode arranged on a side of the first substrate close to the second substrate, a second electrode arranged on a side of the second substrate close to the first substrate, and a ground electrode arranged on a side of the second substrate away from the first substrate; Wherein, the dielectric layer includes liquid crystal molecules, and the first electrode and the second electrode are used to control the deflection of the liquid crystal molecules according to the received voltage; The first electrode comprises: periodically arranged metal patches, and the second electrode is a microstrip line; The long axis direction of the microstrip line is the same as the arrangement direction of the metal patch, and the long axis direction of the metal patch intersects with the long axis direction of the microstrip line; The width of the metal patch is 0.5-1.5 mm, and the length is less than or equal to 5 times the width of the microstrip line; the period of the metal patch is less than or equal to 3 mm.

2. The phase shifter according to claim 1, characterized in that: The thickness of the dielectric layer is 5-10 microns.

3. The phase shifter according to claim 1, characterized in that The ground electrode is a ground wire and is in a planar shape.

4. The phase shifter according to claim 1, characterized in that: The liquid crystal molecules are nematic liquid crystal molecules.

5. A method for operating a phase shifter, characterized in that: The phase shifter according to any one of claims 1 to 4 comprises: An electric signal is applied to the first electrode and the second electrode to make the long axis of the liquid crystal molecules parallel to the direction of the electric field between the first electrode and the second electrode.

6. An antenna, characterized in that: include: At least one phase shifter as claimed in any one of claims 1 to 4.

7. A communication device, characterized in that: include: The antenna as claimed in claim 6.

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